The middle primary germ layer is called MESODERM, which gives rise to a gelatinous material called MESENCHYME, which then gives rise to different types of connective tissue such as bone, cartilage, and blood.
B- Electron transport chain
Answer: B. They allow for specific substance to travel throughout the cell.
Explanation: I know this because carrier proteins and channel proteins are some types of embedded proteins.
B!!!!!!!!!!!!!!!!!!!!!!!!!!
